When they had Deangelo Williams there wasn't such a drop-off. They probably will replace Ridley with another veteran, but I think Conner and Samuels will be fine. However, if they like a RB in the draft, I wouldn't complain if they drafted him as neither of them are anything special.
The same problems the team has now are the same problems they've had for nearly a decade now. Nothing will change without a coaching change.
i'm not sure where the all the hate on the running game came from, considering that Lev Bell left them hung out to dry. Conner and Samuels were pretty darn good. i don't know what the rushing offense ranked but i feel like, before Conner was injured, was doing great. adding a veteran RB that doesn't have fumble issues is really all they need, and then draft another one late (after the 4th round). the O-line is solid so the running game should only get better.
i don't know if Butler is going to be shown the door but i'd be fine with that. we know Tomlin isn't going anywhere (although i'd be fine if the powers that be made that move. there's enough HC openings that Tomlin would not be unemployed for long)
this season was simply a culmination of bad coaching, timely turnovers by Ben (and plenty of others), bad special teams, etc. several plays come to mind that really define this season (in no particular order and i'm going from memory)
1. Conner fumbling in 4th quarter vs the Browns
2. Grimble fumbling out of the endzone vs. the Broncos
3. Boswell missed FG to tie the game vs the Raiders
4. Chargers gift TD on a play that should have been a false start
5. Haden's two PI penalties vs the Saints
i'm sure there are plenty of others.
either way, this season was one of the most disappointing in memory, considering the talent on this team.